I agree with Ken, if you can wait hold out for an 86 or later 5 cylinder version. I had a 86 190D for 5 years and 125K miles and was very happy with it. The 5 cylinder non turbo is 90HP and I think the turbo is 120HP, I'm not sure what the rating for the OM601 version is but I would guess 60-70 HP.

My 190D with a 5 speed manual would routinely get 40+ MPG. The 201 chassis is quite a deal these days - seems like you can get a nice example for 2-3K.